Permanent well completion apparatus



Sept. 29, 1959 c. B. CORLEY, JR., ETAL 2,906,343

PERMANENT WELL COMPLETION APPARATUS Filed April 16, 1958 INVENTORS.

CHARLES B. CORLEY JR., JOHN W. KENNEDAY,

/ BY A/M ATTORNEY United States Patent PERMANENT WELL COMPLETION APPARATUS Charles B. Corley, Jr., and John W. Kenneday, Houston,

Tex., assignors, by mesne assignments, to Jersey Production Research Company, Tulsa, Okla., a corporation of Delaware Application April 16, 1958, Serial No. 728,947

1 Claim. (Cl. 166-115) cent said lower packer adapted to seal ofi the annulus between said outer concentric tubing and the wall of the bore of said lower packer and an opening below said lower packer adapted to fluidly communicate the annulus between said inner and outer concentric tubings and the casing below said lower packer.

An object of this invention is to provide improved dual completion apparatus for working over and servicing a lower productive interval of a dually completed well.

This and other objects of the invention will be apparent from a description of the invention taken 'in conjunction with the drawing, wherein the sole figure is a crosssectional view of a well bore having the dual completion apparatus arranged therein. v

Referring more particularly to the drawing, the figure I illustrates a cased borehole penetrating a plurality of subsurface formations including productive zones orinare set permanently during the life of the well and various producing workover and servicing operations are performed through these permanently set tubing strings. The workover and servicing operations generally performed on permanently completed wells include squeeze cementing operations, wherein perforations below the lower end of the tubing are cemented off, perforating or reperforating by means of wireline guns at the same or diiferent producing zones or intervals, sand washing operations, acidizing operations, and other remedial work. A full discussion of permanent well completion operations is described in Permanent Well Completions and Wireline Operations, The Petroleum Engineer, September 1956.

This invention particularly relates to one type of permanent well completion operation, termed dual completion herein, wherein upper and lower productive zones or intervals are completed at the same time. In the particular type of dual completion operation described herein, two parallel, eccentric, coextensive tubing strings are permanently set above the uppermost productive interval, a single bore packer is arranged below the uppermost productive interval and above a lower productive interval and means are arranged in the tubing strings for controlling the direction of fluid flow.

Briefly, this invention comprises apparatus for working over and servicing a cased borehole penetrating a plurality of spaced-apart hydrocarbon productive intervals having two parallelly extending, eccentric, spacedapart, co-extensive tubing strings arranged therein, the lower open ends of which are positioned above the uppermost productive interval. The apparatus includes a lower packer having a single bore therethrough arranged between the upper and lower productive intervals; a lateral passage fluidly communicating the tubing strings; a flow directing member or choke arranged in one of the tubing strings, the flow directing member having a closed lower end and open upper end and an opening intermediate the length thereof fluidly communicating with said passage and being provided with upper and lower sealing means adapted to seal off the annulus between said tubing string and said flow directing means, respectively, above and below said passage; and a tubular extension sealingly supported in said other tubing string and ex tending through the bore of said lower packer, said tubular extension including concentric tubings, the outer tubing being provided with an opening adjacent said passage, first sealing means adapted to seal off the annulus between said outer concentric tubing and said other tubing string below said passage, second sealing means adjatervals 11 and 12. The casing 13 is perforated as at 14 and 15, which perforations extend into zones 11 and 12, respectively. Parallelly extending, co-extensive, eccentric tubing strings 16 and 17 are arranged in casing 13, with their lower ends positioned above the uppermost productive zone 11. The upper ends of tubing strings 16 and, 17 are supported by and suspended from dual wellhead equipment, not shown, arranged on the surface of the earth. A dual bore packer 20 may be provided to embrace the lower ends of the tubings 16 and 17. Tubing strings 16 and 17 are provided with ports 18 and 19, respectively, which fluid-1y communicate the interior of the tubings by way of'lateral passageway 23 provided in packer 20. Upper packer 20 is not necessarily a part of the dual completion apparatus and may be replaced by any suitable mandrel providing fluid communication between the two tubing strings.

Arranged between zones 11 and 12 is a lower packer 24 provided with a single bore 25.

Tubing strings 16 and 17 are provided with landing nipples 26 and. 27, respectively, positioned a suitable distance above the packer 20. These landing nipples may be of any desirable type for supporting tubular extension members, flow directing members and the like, for example, the landing nipple disclosed in the Composite Catalog, vol. 1 (1952S3), 19th ed. on page 4063 is suitable for use.

A tubular extension, generally designated 30, is arranged in tubing 16 and supported by landing nipple 26. The extension member 30 is formed of inner and outer concentric tubes 31 and 32, respectively, and is provided with a fishing head 29 adjacent its upper end. Tubes 31 and 32 form an annular fluid passage 37 there between. Sealing means 28 is arranged on extension member 30 to sealingly engage the inner Wall of tubing 16 above the port 18.

Outer concentric tube 32 is formed to provide openings 33 near its upper end adjacent port 18. Also the outer tube 32 is provided with sealing means 34 adapted to seal off the annulus between the outer tube 32 and tubing 16 below the port 18.

The lower end of tubular extension member 30 extends through the bore '25 of lower packer 24. The outer tube 32 is provided with spaced-apart sealing means 3535 which sealingly engage the wall of bore 25. The tube 32 also is formed to provide ports 46 positioned between the seals 3535. Tube 32 is provided with openings 36 which are positioned below packer 24. In the position shown openings 36 are closed by a sleeve piston valve member 39 providedwith sealing means 48, 49 and 50. A spring 51 tends to bias the sleeve valve downwardly to the open position but is initially retained by a shear pin 52. The purpose of valve member 39 will herein later be explained.

A flow directing member 40 is supported in tubing Patented Sept. 29, 1959 t 3 string 17 by landing nipple 27. Member 40 is provided with a fishing head 41 and a closed lower end 42. As shown, member 45) is provided with sealing means 44 and 45 which sealingly engage the wall of tubing 17 above and below the port '19. The member 40 is formed to provide ports 43 positioned between the seals 44 and 45. The tubing string 17 is therefore in fluid communication with tubing string 16 by way of ports 43 and lateral passageway 23 of packer 20.

When it is desired to work over lower zone 12, as for example a cementing operation, it is first desirable to seal test the various sealing means mentioned including the seals 35-35 in the bore of packer 24. It is for this purpose that the sleeve valve 39 is provided. The shear pin 52 is capable of withstanding this test pressure. After testing, additional pressure shears the pin 52 allowing the sleeve valve to open ports 36. These ports then remain open during subsequent operations.

A cement slurry may be now ptunped down tubing string 16 through the open upper end of tubular extension 30, through the inner tube 31 and into the casing adjacent interval 12.. For reverse circulating out the excess cement, the direction of fluid flow may be down the tubing string 17 through the open upper end of flow directing means 40 through openings 43, port 19, passageway 23, port 18, openings 33 in tube 32, downwardly through annulus 37 out the ports 36 below the packer 24 into the casing and then up inner tube 31, through the open upper end of extension 39 and through the tubing 16 to the surface of the earth.

Having fully described the apparatus, objects and operation of our invention, we claim:

Apparatus for working over and servicing a cased borehole penetrating a plurality of spaced-apart hydrocarbon productive intervals comprising first and second spaced-apart tubing strings arranged in said borehole, the lower open ends of said tubing strings being positioned above an upper productive interval, a first packer provided with spaced-apart bores arranged on said tubing strings adapted to seal off the space between said tubing strings and said casing, a second packer provided with a bore therethrough arranged in said borehole between said upper productive interval and a lower productive interval adapted to seal off the space between the bore of said second packer and said casing, means interconnecting said tubing strings providing a flow passage between said tubing strings isolated from the annulus between said tubing strings and said casing, a tubing extension arranged in said first tubing string and extending through the bore of said second packer, means for supporting said tubing extension in said first tubing string, first sealing means arranged on said tubing extension adapted to seal off the annulus between said tubing extension and said first tubing string above said passage, said tubing extension including concentric tubings, said inner tubing being open ended and extending from above said first sealing means to below said second packer, said outer concentric tubing extending from below said first sealing means to below said second packer and being provided with a first opening adjacent to and in fluid communication with said passage and a second opening below said second packer fluidly communicating with said casing, second sealing means adjacent said passage adapted to seal off the annulus between said outer tubing and said first tubing string below said passage, third sealing means adjacent said second packer adapted to seal off the annulus between said outer tubing and the bore wall of said second packer, a choke supported in said second tubing string adjacent said passage, said choke being provided with an open upper end, a closed lower end, and an opening intermediate the length thereof, said choke intermediate opening fluidly communicating with said passage, and fourth sealing means arranged on said choke adapted to seal ofl? the annulus between said choke and said second tubing string below said passage.

References Cited in the file of this patent UNITED STATES PATENTS 2,749,989 Huber June 12, 1956 2,760,578 Tausch Aug. 28, 1956 2,785,754 True Mar. 19, 1957 Anew-e 

